Lean Six Sigma Yellow Belt Certification The Measure Phase 3 — Questions and Answers
Question 1: The Cp index measures process capability without regard to centering. What additional index accounts for process centering?
- Cpk (Correct answer)
- Cpm
- Pp
- Sigma
Correct answer: Cpk
Cpk adjusts for the process mean's location relative to the specification limits, penalizing a process that is off-center.
Question 2: Which tool is used in the Measure phase to visually show where defects occur on a physical product or diagram?
- Histogram
- Defect concentration diagram (measles chart) (Correct answer)
- Scatter plot
- Box plot
Correct answer: Defect concentration diagram (measles chart)
A defect concentration diagram (measles chart) marks defect locations on a drawing of the product to reveal spatial patterns.
Question 3: When establishing a baseline process capability, which condition must be met first?
- The process must be profitable
- The process must be in statistical control (Correct answer)
- The process must meet customer specs
- The sample size must exceed 1,000 units
Correct answer: The process must be in statistical control
Process capability indices are only meaningful when the process is stable (in statistical control), otherwise capability calculations are invalid.
Question 4: A box plot (box-and-whisker plot) displays all of the following EXCEPT:
- Median
- Interquartile range
- Outliers
- Exact raw data values (Correct answer)
Correct answer: Exact raw data values
Box plots summarize the distribution showing median, quartiles, range, and outliers, but they do not display individual raw data values.
Question 5: In process mapping during the Measure phase, a 'value-added' step is one that:
- Reduces cycle time
- Transforms the product in a way the customer cares about and would pay for (Correct answer)
- Eliminates rework
- Is required by regulatory bodies
Correct answer: Transforms the product in a way the customer cares about and would pay for
A value-added step physically transforms the product or service in a way the customer recognizes and is willing to pay for.
Question 6: Which measurement scale has a true zero point and allows meaningful ratio comparisons?
- Nominal
- Ordinal
- Interval
- Ratio (Correct answer)
Correct answer: Ratio
A ratio scale has a true zero point, meaning zero represents absence of the attribute, enabling meaningful ratios (e.g., 20 kg is twice 10 kg).
Question 7: What does a high Gauge R&R percentage (e.g., >30%) relative to total variation indicate?
- The measurement system is acceptable
- The measurement system contributes too much variation and needs improvement (Correct answer)
- Part-to-part variation is the dominant source
- The gauge is highly precise
Correct answer: The measurement system contributes too much variation and needs improvement
When Gauge R&R exceeds 30% of total variation, the measurement system is considered unacceptable and must be improved before data is reliable.
Lean Six Sigma Yellow Belt Certification The Measure Phase 3
The Cp index measures process capability without regard to centering.
What additional index accounts for process centering?